RESUMO
Oxidative damage theory is currently one of the predominant theories on the mechanisms of aging. Previous research has shown that antioxidants can extend the lifespan in the model organism by scavenging free radicals,inducing the expression of stress related genes and hormesis. However, recent studies have suggested that these pharmaceuticals may cause serious side effects,such as promoting oxidation,increasing the risk of cancer,and destroying the metabolic balance. The low absorption and targeting property also limit the efficiency of most antioxidants. As a result ,the correlation between antioxidants and lifespan extension remains to be demonstrated. We reviewed the research progress in the field of lifespan extension by antioxidants in recent years and provided references for future research in related areas.
RESUMO
Alpha-ketoglutarate (AKG) is a key molecule in the Krebs cycle determining the overall rate of the citric acid cycle of the organism. It is a nitrogen scavenger and a source of glutamate and glutamine that stimulates protein synthesis and inhibits protein degradation in muscles. AKG as a precursor of glutamate and glutamine is a central metabolic fuel for cells of the gastrointestinal tract as well. AKG can decrease protein catabolism and increase protein synthesis to enhance bone tissue formation in the skeletal muscles and can be used in clinical applications. In addition to these health benefits, a recent study has shown that AKG can extend the lifespan of adult Caenorhabditis elegans by inhibiting ATP synthase and TOR. AKG not only extends lifespan, but also delays age-related disease. In this review, we will summarize the advances in AKG research field, in the content of its physiological functions and applications.